Database Index Overhead: Write Amplification, Cache Pressure, and Maintenance Costs Database indexes are routinely treated as default performance remedies for sluggish queries. When a query scan latency spikes, developers add an index without evaluating the systemic tax imposed on the write path. Every secondary index transforms a localized write operation into a multi-page routing problem across storage engines, transaction logs, and memory buffers. Unchecked indexing induces severe write a...